UAVs can be used for a variety of tasks, including surveillance, reconnaissance, photography, videography, emergency responding, delivery of articles, and other tasks. Various sensors may be placed on UAVs for remote data collection. The data may be stored in UAV memory or streamed to a user operating UAV in real time.
The use of UAVs for collecting audio data is hindered by acoustic interference from propellers, motors, and other static and dynamic operating components of the UAVs. Prior art solutions to reduce noise from these components are complex, leading to impractical costs, size, and, or weight. Prior art generally relates to active noise cancellation, such as the use of phased arrays of a plurality of microphone sources to measure and subtract ambient noise in real time.
By way of example, U.S. Patent Application 2016/0063987 A1 “UNMANNED AERIAL VEHICLE (UAV) FOR COLLECTING AUDIO DATA” describes a noise-cancellation system using at least two microphones and a relatively complex low-latency microprocessor to perform the active noise cancellation function.
The complexity of noise-cancellation systems of the prior art leads to increased manufacturing costs of UAV systems. Furthermore, required high clock speeds of microprocessors used by noise cancellation systems of the prior art may increase energy consumption of UAVs, which affects autonomous flight time and the range of flight of the UAVs.